Computer system for generating print data for printing interactive document

ABSTRACT

A computer system for generating print data for an interactive document. The computer being is configured for: receiving a print request from a user; formatting user information in an electronic document so as to include a first user interactive element; determining advertising material for printing with the user information; formatting the advertising material so as to include a second user interactive element; and generating print data for printing the formatted user information and the formatted advertising material together with coincident coded data on a substrate. The coded data is readable by a sensing device and is indicative of a document identity and the first and second interactive elements.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/835,408 filed Jul. 13, 2010, which is a continuation of U.S.application Ser. No. 11/706,964 filed Feb. 16, 2007, now issued U.S.Pat. No. 7,760,371, which is a continuation of U.S. application Ser. No.09/693,415 filed on Oct. 20, 2000, now issued U.S. Pat. No. 7,190,474all of which are herein incorporated by reference.

FIELD OF INVENTION

The present invention relates generally to electronically deliveredprinted documents and, more particularly, to a method and system for theautomatic placement of advertising in otherwise empty space in suchprinted documents.

CO-PENDING APPLICATIONS

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications/granted patentsfiled by the applicant or assignee of the present invention with thepresent invention:

7,190,474 7,110,126 6,813,558 6,965,454 6,847,883 7,131,058 7,533,0316,982,798 6,474,888 6,627,870 6,724,374 7,369,265 6,454,482 6,808,3306,527,365 6,474,773 6,550,997

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications/granted patentsfiled by the applicant or assignee of the present invention on Sep. 15,2000:

6,679,420 6,963,845 6,995,859 6,720,985

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications/granted patentsfiled by the applicant or assignee of the present invention on Jun. 30,2000:

6,824,044 6,678,499 6,976,220 6,976,035 6,766,942 7,286,113 6,922,7796,978,019 7,406,445 6,959,298 6,973,450 7,150,404 6,965,882 7,233,9247,007,851 6,957,921 6,457,883 6,831,682 6,977,751 6,398,332 6,394,5736,622,923

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications/granted patentsfiled by the applicant or assignee of the present invention on 23 May2000:

6,428,133 6,526,658 6,315,399 6,338,548 6,540,319 6,328,431 6,328,4256,991,320 6,383,833 6,464,332 6,390,591 7,018,016 6,328,417 7,721,9487,079,712 6,980,318 6,825,945 7,330,974 6,813,039 6,987,506 7,038,7977,173,722 6,816,274 7,102,772 7,350,236 6,681,045 6,728,000 6,789,1917,088,459 7,707,082 7,068,382 7,062,651 6,789,194 6,987,573 6,644,6426,502,614 6,622,999 6,669,385 6,549,935 6,290,349 6,727,996 6,591,8846,439,706 6,760,119 7,295,332 7,055,739 6,428,155 6,785,016 6,870,9666,822,639 6,737,591 7,456,820 7,233,320 6,830,196 6,832,717 6,957,7686,281,912 6,604,810 7,170,499 7,106,888 7,123,239 6,409,323 6,859,2897,154,638 6,318,920 6,488,422 6,795,215

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

BACKGROUND

Advertising has traditionally been distributed in printed publications,and typically placed to exploit the editorial context, the locality ofthe publication's distribution, and the demographic of its readership.

In more recent times advertising has been distributed as part of Webpages. The Web page advertising space is typically specificallyallocated for, and dedicated to, advertising. Advertisements typicallyare often customised and targeted based on the page being viewed or thesearch being carried out by the user. If the user is registered with thesite the advertising may be targeted to the user's demographic based onthe user's known profile.

SUMMARY OF INVENTION

It is an objective of the present invention to provide a new method andsystem for advertising.

In a first aspect, the present invention provides a method of producinga document by formatting user requested information in the document soas to include one user interactive element, to allow the user to effecta response to the information, using a sensing device for transmittingresponse data back to a computer system, including:

identifying an advertising space, outside an area of the document to beoccupied by the information; and

printing the document with advertising material in the space.

Preferably, the advertising space is determined to be on a reverse sideof the document relative to the user requested information.

Preferably also, the information is formatted at a publication server ofthe computer system and the method includes the publication servermonitoring the said area and, once the space is identified, receivingthe advertising material from an advertising server, for inclusion inthe document.

Preferably also, the document is printed with coded data, for sensing bythe sensing device, indicative of an identity of the document and of theat least one interactive element. Preferably also, the document isprinted on a surface defining structure at the same time as the codeddata is printed on the surfaces. Preferably also, the method includesincluding retaining a retrievable record of the printed document, thedocument being retrievable using the identity data as contained in thecoded data.

Preferably also, wherein the sensing device includes an identificationcode specific to a particular user and the method includes monitoringuse of the sensing device in the computer system.

In a second aspect, the present invention provides a system forproducing a document, including:

a computer system for formatting user requested information in thedocument so as to include at least one user interactive element, toallow the user to effect a response to the information, using a sensingdevice for transmitting response data back to the computer system,wherein the computer system is arranged to identify an advertisingspace, outside an area of the document to be occupied by the informationand to effect printing of the document with advertising material in saidspace.

Preferably, the system includes a printer adapted to print on both sidesof the document, in order to print the advertising material on a reverseside of the document, relative to the user requested information.

Preferably also, the computer system includes a publication server forformatting the document and an advertising server for providing theadvertising material, wherein the publication server monitors said areaand receives advertising material from the advertising server, forinclusion in the document.

Preferably also, the document includes coded data indicative of anidentity of the document and of the at least one interactive element.Preferably also, the printer is arranged to print the coded data at thesame time as printing the document on a surface defining structure.Preferably also, wherein the coded data is substantially invisible inthe visible spectrum. Preferably also, the system includes a databasefor keeping a retrievable record of each document generated, eachdocument being retrievable by using its identity, as included in thecoded data.

Accordingly, the present invention provides a method and system whichutilizes one or more forms capable of interacting with a computersystem. Whilst the novel method and system of the present invention maybe used in conjunction with a single computer system, in a particularlypreferred form it is designed to operate over a computer network, suchas the Internet.

BRIEF DESCRIPTION OF DRAWINGS

Preferred and other embodiments of the invention will now be described,by way of non-limiting example only, with reference to the accompanyingdrawings, in which:

FIG. 1 is a schematic of a the relationship between a sample printednetpage and its online page description;

FIG. 2 is a schematic view of a interaction between a netpage pen, anetpage printer, a netpage page server, and a netpage applicationserver;

FIG. 3 is a schematic view of a high-level structure of a printednetpage and its online page description;

FIG. 4A is a plan view showing a structure of a netpage tag;

FIG. 4B is a plan view showing a relationship between a set of the tagsshown in FIG. 4A and a field of view of a netpage sensing device in theform of a netpage pen;

FIG. 5A is a plan view showing an alternative structure of a netpagetag;

FIG. 5B is a plan view showing a relationship between a set of the tagsshown in FIG. 5A and a field of view of a netpage sensing device in theform of a netpage pen;

FIG. 5C is a plan view showing an arrangement of nine of the tags shownin FIG. 5A where targets are shared between adjacent tags;

FIG. 5D is a plan view showing the interleaving and rotation of thesymbols of the four codewords of the tag shown in FIG. 5A;

FIG. 6 is a example of an advertisement placed within free space on apage; and

FIG. 7 is an example of an advertisement placed on the reverse-side of apage.

DETAILED DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

Note: Memjet™ is a trademark of Silverbrook Research Pty Ltd, Australia.

In the preferred embodiment, the invention is configured to work withthe netpage networked computer system, a summary of which is given belowand a detailed description of which is given in our earlierapplications, including in particular applications U.S. Pat. No.7,233,320, U.S. Pat. No. 6,870,966, U.S. Pat. No. 6,727,996, U.S. Ser.No. 09/575,195 and U.S. Pat. No. 6,428,133. It will be appreciated thatnot every implementation will necessarily embody all or even most of thespecific details and extensions described in these applications inrelation to the basic system. However, the system is described in itsmost complete form to assist in understanding the context in which thepreferred embodiments and aspects of the present invention operate.

In brief summary, the preferred form of the netpage system employs acomputer interface in the form of a mapped surface, that is, a physicalsurface which contains references to a map of the surface maintained ina computer system. The map references can be queried by an appropriatesensing device. Depending upon the specific implementation, the mapreferences may be encoded visibly or invisibly, and defined in such away that a local query on the mapped surface yields an unambiguous mapreference both within the map and among different maps. The computersystem can contain information about features on the mapped surface, andsuch information can be retrieved based on map references supplied by asensing device used with the mapped surface. The information thusretrieved can take the form of actions which are initiated by thecomputer system on behalf of the operator in response to the operator'sinteraction with the surface features.

In its preferred form, the netpage system relies on the production of,and human interaction with, netpages. These are pages of text, graphicsand images printed on ordinary paper or other media, but which work likeinteractive web pages. Information is encoded on each page using inkwhich is substantially invisible to the unaided human eye. The ink,however, and thereby the coded data, can be sensed by an opticallyimaging pen and transmitted to the netpage system.

In the preferred form, active buttons and hyperlinks on each page can beclicked with the pen to request information from the network or tosignal preferences to a network server. In one embodiment, text writtenby hand on a netpage is automatically recognized and converted tocomputer text in the netpage system, allowing forms to be filled in. Inother embodiments, signatures recorded on a netpage are automaticallyverified, allowing e-commerce transactions to be securely authorized.

As illustrated in FIG. 1, a printed netpage 1 can represent ainteractive form which can be filled in by the user both physically, onthe printed page, and “electronically”, via communication between thepen and the netpage system. The example shows a “Request” formcontaining name and address fields and a submit button. The netpageconsists of graphic data 2 printed using visible ink, and coded data 3printed as a collection of tags 4 using invisible ink. The correspondingpage description 5, stored on the netpage network, describes theindividual elements of the netpage. In particular it describes the typeand spatial extent (zone) of each interactive element (i.e. text fieldor button in the example), to allow the netpage system to correctlyinterpret input via the netpage. The submit button 6, for example, has azone 7 which corresponds to the spatial extent of the correspondinggraphic 8.

As illustrated in FIG. 2, the netpage pen 101, a preferred form of whichis described in our earlier application U.S. Ser. No. 09/575,174, worksin conjunction with a netpage printer 601, an Internet-connectedprinting appliance for home, office or mobile use. The pen is wirelessand communicates securely with the netpage printer via a short-rangeradio link 9.

The netpage printer 601, preferred forms of which are described in ourearlier application U.S. Pat. No. 6,727,996 and our co-filed applicationU.S. Ser. No. 09/693,514, is able to deliver, periodically or on demand,personalized newspapers, magazines, catalogs, brochures and otherpublications, all printed at high quality as interactive netpages.Unlike a personal computer, the netpage printer is an appliance whichcan be, for example, wall-mounted adjacent to an area where the morningnews is first consumed, such as in a user's kitchen, near a breakfasttable, or near the household's point of departure for the day. It alsocomes in tabletop, desktop, portable and miniature versions.

Netpages printed at their point of consumption combine the ease-of-useof paper with the timeliness and interactivity of an interactive medium.

As shown in FIG. 2, the netpage pen 101 interacts with the coded data ona printed netpage 1 and communicates, via a short-range radio link 9,the interaction to a netpage printer. The printer 601 sends theinteraction to the relevant netpage page server 10 for interpretation.In appropriate circumstances, the page server sends a correspondingmessage to application computer software running on a netpageapplication server 13. The application server may in turn send aresponse which is printed on the originating printer.

The netpage system is made considerably more convenient in the preferredembodiment by being used in conjunction with high-speedmicroelectromechanical system (MEMS) based inkjet (Memjet™) printers,described in our earlier application U.S. Pat. No. 6,428,133. In thepreferred form of this technology, relatively high-speed andhigh-quality printing is made more affordable to consumers. In itspreferred form, a netpage publication has the physical characteristicsof a traditional newsmagazine, such as a set of letter-size glossy pagesprinted in full color on both sides, bound together for easy navigationand comfortable handling.

The netpage printer exploits the growing availability of broadbandInternet access. The netpage printer can also operate with slowerconnections, but with longer delivery times and lower image quality. Thenetpage system can also be enabled using existing consumer inkjet andlaser printers, although the system will operate more slowly and willtherefore be less acceptable from a consumer's point of view. In otherembodiments, the netpage system is hosted on a private intranet. Instill other embodiments, the netpage system is hosted on a singlecomputer or computer-enabled device, such as a printer.

Netpage publication servers 14 on the netpage network are configured todeliver print-quality publications to netpage printers. Periodicalpublications are delivered automatically to subscribing netpage printersvia pointcasting and multicasting Internet protocols. Personalizedpublications are filtered and formatted according to individual userprofiles.

A netpage printer can be configured to support any number of pens, and apen can work with any number of netpage printers. In the preferredimplementation, each netpage pen has a unique identifier. A householdmay have a collection of colored netpage pens, one assigned to eachmember of the family. This allows each user to maintain a distinctprofile with respect to a netpage publication server or applicationserver.

A netpage pen can also be registered with a netpage registration server11 and linked to one or more payment card accounts. This allowse-commerce payments to be securely authorized using the netpage pen. Thenetpage registration server compares the signature captured by thenetpage pen with a previously registered signature, allowing it toauthenticate the user's identity to an e-commerce server. Otherbiometrics can also be used to verify identity. A version of the netpagepen includes fingerprint scanning, verified in a similar way by thenetpage registration server.

Although a netpage printer may deliver periodicals such as the morningnewspaper without user intervention, it can be configured never todeliver unsolicited junk mail. In its preferred form, it only deliversperiodicals from subscribed or otherwise authorized sources. In thisrespect, the netpage printer is unlike a fax machine or e-mail accountwhich is visible to any junk mailer who knows the telephone number ore-mail address.

Each object model in the system is described using a Unified ModelingLanguage (UML) class diagram. A class diagram consists of a set ofobject classes connected by relationships, and two kinds ofrelationships are of interest here: associations and generalizations. Anassociation represents some kind of relationship between objects, i.e.between instances of classes. A generalization relates actual classes,and can be understood in the following way: if a class is thought of asthe set of all objects of that class, and class A is a generalization ofclass B, then B is simply a subset of A. Each class is drawn as arectangle labelled with the name of the class. It contains a list of theattributes of the class, separated from the name by a horizontal line,and a list of the operations of the class, separated from the attributelist by a horizontal line. In the class diagrams which follow, however,operations are never modelled. An association is drawn as a line joiningtwo classes, optionally labelled at either end with the multiplicity ofthe association. The default multiplicity is one. An asterisk (*)indicates a multiplicity of “many”, i.e. zero or more. Each associationis optionally labelled with its name, and is also optionally labelled ateither end with the role of the corresponding class. An open diamondindicates an aggregation association (“is-part-of”), and is drawn at theaggregator end of the association line. A generalization relationship(“is-a”) is drawn as a solid line joining two classes, with an arrow (inthe form of an open triangle) at the generalization end. When a classdiagram is broken up into multiple diagrams, any class which isduplicated is shown with a dashed outline in all but the main diagramwhich defines it. It is shown with attributes only where it is defined.

Netpages are the foundation on which a netpage network is built. Theyprovide a paper-based user interface to published information andinteractive services. A netpage consists of a printed page (or othersurface region) invisibly tagged with references to an onlinedescription of the page. The online page description is maintainedpersistently by a netpage page server. The page description describesthe visible layout and content of the page, including text, graphics andimages. It also describes the input elements on the page, includingbuttons, hyperlinks, and input fields. A netpage allows markings madewith a netpage pen on its surface to be simultaneously captured andprocessed by the netpage system.

Multiple netpages can share the same page description. However, to allowinput through otherwise identical pages to be distinguished, eachnetpage is assigned a unique page identifier. This page ID hassufficient precision to distinguish between a very large number ofnetpages.

Each reference to the page description is encoded in a printed tag. Thetag identifies the unique page on which it appears, and therebyindirectly identifies the page description. The tag also identifies itsown position on the page. Characteristics of the tags are described inmore detail below.

Tags are printed in infrared-absorptive ink on any substrate which isinfrared-reflective, such as ordinary paper. Near-infrared wavelengthsare invisible to the human eye but are easily sensed by a solid-stateimage sensor with an appropriate filter.

A tag is sensed by an area image sensor in the netpage pen, and the tagdata is transmitted to the netpage system via the nearest netpageprinter. The pen is wireless and communicates with the netpage printervia a short-range radio link. Tags are sufficiently small and denselyarranged that the pen can reliably image at least one tag even on asingle click on the page. It is important that the pen recognize thepage ID and position on every interaction with the page, since theinteraction is stateless. Tags are error-correctably encoded to makethem partially tolerant to surface damage.

The netpage page server maintains a unique page instance for eachprinted netpage, allowing it to maintain a distinct set of user-suppliedvalues for input fields in the page description for each printednetpage.

The relationship between the page description, the page instance, andthe printed netpage is shown in FIG. 3. The printed netpage may be partof a printed netpage document 45. The page instance is associated withboth the netpage printer which printed it and, if known, the netpageuser who requested it.

In a preferred form, each tag identifies the region in which it appears,and the location of that tag within the region. A tag may also containflags which relate to the region as a whole or to the tag. One or moreflag bits may, for example, signal a tag sensing device to providefeedback indicative of a function associated with the immediate area ofthe tag, without the sensing device having to refer to a description ofthe region. A netpage pen may, for example, illuminate an “active area”LED when in the zone of a hyperlink.

In a preferred embodiment, each tag contains an easily recognizedinvariant structure which aids initial detection, and which assists inminimizing the effect of any warp induced by the surface or by thesensing process. The tags preferably tile the entire page, and aresufficiently small and densely arranged that the pen can reliably imageat least one tag even on a single click on the page. It is importantthat the pen recognize the page ID and position on every interactionwith the page, since the interaction is stateless.

In a preferred embodiment, the region to which a tag refers coincideswith an entire page, and the region ID encoded in the tag is thereforesynonymous with the page ID of the page on which the tag appears. Inother embodiments, the region to which a tag refers can be an arbitrarysubregion of a page or other surface. For example, it can coincide withthe zone of an interactive element, in which case the region ID candirectly identify the interactive element.

Each tag contains typically contains 16 bits of tag ID, at least 90 bitsof region ID, and a number of flag bits. Assuming a maximum tag densityof 64 per square inch, a 16-bit tag ID supports a region size of up to1024 square inches. Larger regions can be mapped continuously withoutincreasing the tag ID precision simply by using abutting regions andmaps. The distinction between a region ID and a tag ID is mostly one ofconvenience. For most purposes the concatenation of the two can beconsidered as a globally unique tag ID. Conversely, it may also beconvenient to introduce structure into the tag ID, for example to definethe x and y coordinates of the tag. A 90-bit region ID allows 2⁹⁰ (˜10²⁷or a thousand trillion trillion) different regions to be uniquelyidentified. Tags may also contain type information, and a region may betagged with a mixture of tag types. For example, a region may be taggedwith one set of tags encoding x coordinates and another set, interleavedwith the first, encoding y coordinates.

In one embodiment, 120 bits of tag data are redundantly encoded using a(15, 5) Reed-Solomon code. This yields 360 encoded bits consisting of 6codewords of 15 4-bit symbols each. The (15, 5) code allows up to 5symbol errors to be corrected per codeword, i.e. it is tolerant of asymbol error rate of up to 33% per codeword. Each 4-bit symbol isrepresented in a spatially coherent way in the tag, and the symbols ofthe six codewords are interleaved spatially within the tag. This ensuresthat a burst error (an error affecting multiple spatially adjacent bits)damages a minimum number of symbols overall and a minimum number ofsymbols in any one codeword, thus maximising the likelihood that theburst error can be fully corrected.

Any suitable error-correcting code can be used in place of a (15, 5)Reed-Solomon code, for example a Reed-Solomon code with more or lessredundancy, with the same or different symbol and codeword sizes;another block code; or a different kind of code, such as a convolutionalcode (see, for example, Stephen B. Wicker, Error Control Systems forDigital Communication and Storage, Prentice-Hall 1995, the contents ofwhich a herein incorporated by cross-reference).

One embodiment of the physical representation of the tag, shown in FIG.4 a and described in our earlier application U.S. Ser. No. 09/575,129,includes fixed target structures 15, 16, 17 and variable data areas 18.The fixed target structures allow a sensing device such as the netpagepen to detect the tag and infer its three-dimensional orientationrelative to the sensor. The data areas contain representations of theindividual bits of the encoded tag data. To maximise its size, each databit is represented by a radial wedge in the form of an area bounded bytwo radial lines and two concentric circular arcs. Each wedge has aminimum dimension of 8 dots at 1600 dpi and is designed so that its base(its inner arc), is at least equal to this minimum dimension. The heightof the wedge in the radial direction is always equal to the minimumdimension. Each 4-bit data symbol is represented by an array of 2×2wedges. The fifteen 4-bit data symbols of each of the six codewords areallocated to the four concentric symbol rings 18 a to 18 d ininterleaved fashion. Symbols are allocated alternately in circularprogression around the tag. The interleaving is designed to maximise theaverage spatial distance between any two symbols of the same codeword.

In order to support “single-click” interaction with a tagged region viaa sensing device, the sensing device must be able to see at least oneentire tag in its field of view no matter where in the region or at whatorientation it is positioned. The required diameter of the field of viewof the sensing device is therefore a function of the size and spacing ofthe tags. Assuming a circular tag shape, the minimum diameter of thesensor field of view 193 is obtained when the tags are tiled on aequilateral triangular grid, as shown in FIG. 4 b.

The tag structure just described is designed to allow both regulartilings of planar surfaces and irregular tilings of non-planar surfaces.Regular tilings are not, in general, possible on non-planar surfaces. Inthe more usual case of planar surfaces where regular tilings of tags arepossible, i.e. surfaces such as sheets of paper and the like, moreefficient tag structures can be used which exploit the regular nature ofthe tiling.

An alternative tag structure more suited to a regular tiling is shown inFIG. 5 a. The tag 4 is square and has four perspective targets 17. It issimilar in structure to tags described by Bennett et al. in U.S. Pat.No. 5,051,746. The tag represents sixty 4-bit Reed-Solomon symbols 47,for a total of 240 bits. The tag represents each one bit as a dot 48,and each zero bit by the absence of the corresponding dot. Theperspective targets are designed to be shared between adjacent tags, asshown in FIGS. 5 b and 5 c. FIG. 5 b shows a square tiling of 16 tagsand the corresponding minimum field of view 193, which must span thediagonals of two tags. FIG. 5 c shows a square tiling of nine tags,containing all one bits for illustration purposes.

Using a (15, 7) Reed-Solomon code, 112 bits of tag data are redundantlyencoded to produce 240 encoded bits. The four codewords are interleavedspatially within the tag to maximize resilience to burst errors.Assuming a 16-bit tag ID as before, this allows a region ID of up to 92bits. The data-bearing dots 48 of the tag are designed to not overlaptheir neighbors, so that groups of tags cannot produce structures whichresemble targets. This also saves ink. The perspective targets thereforeallow detection of the tag, so further targets are not required.

Although the tag may contain an orientation feature to allowdisambiguation of the four possible orientations of the tag relative tothe sensor, it is also possible to embed orientation data in the tagdata. For example, the four codewords can be arranged so that each tagorientation contains one codeword placed at that orientation, as shownin FIG. 5 d, where each symbol is labelled with the number of itscodeword (1-4) and the position of the symbol within the codeword (A-O).Tag decoding then consists of decoding one codeword at each orientation.Each codeword can either contain a single bit indicating whether it isthe first codeword, or two bits indicating which codeword it is. Thelatter approach has the advantage that if, say, the data content of onlyone codeword is required, then at most two codewords need to be decodedto obtain the desired data. This may be the case if the region ID is notexpected to change within a stroke and is thus only decoded at the startof a stroke. Within a stroke only the codeword containing the tag ID isthen desired. Furthermore, since the rotation of the sensing devicechanges slowly and predictably within a stroke, only one codewordtypically needs to be decoded per frame.

It is possible to dispense with perspective targets altogether andinstead rely on the data representation being self-registering. In thiscase each bit value (or multi-bit value) is typically represented by anexplicit glyph, i.e. no bit value is represented by the absence of aglyph. This ensures that the data grid is well-populated, and thusallows the grid to be reliably identified and its perspective distortiondetected and subsequently corrected during data sampling. To allow tagboundaries to be detected, each tag data must contain a marker pattern,and these must be redundantly encoded to allow reliable detection. Theoverhead of such marker patterns is similar to the overhead of explicitperspective targets. One such scheme uses dots positioned a variouspoints relative to grid vertices to represent different glyphs and hencedifferent multi-bit values (see Anoto Technology Description, AnotoApril 2000).

Decoding a tag results in a region ID, a tag ID, and a tag-relative pentransform. Before the tag ID and the tag-relative pen location can betranslated into an absolute location within the tagged region, thelocation of the tag within the region must be known. This is given by atag map, a function which maps each tag ID in a tagged region to acorresponding location. A tag map reflects the scheme used to tile thesurface region with tags, and this can vary according to surface type.When multiple tagged regions share the same tiling scheme and the sametag numbering scheme, they can also share the same tag map. The tag mapfor a region must be retrievable via the region ID. Thus, given a regionID, a tag ID and a pen transform, the tag map can be retrieved, the tagID can be translated into an absolute tag location within the region,and the tag-relative pen location can be added to the tag location toyield an absolute pen location within the region.

The tag ID may have a structure which assists translation through thetag map. It may, for example, encoded cartesian coordinates or polarcoordinates, depending on the surface type on which it appears. The tagID structure is dictated by and known to the tag map, and tag IDsassociated with different tag maps may therefore have differentstructures.

Two distinct surface coding schemes are of interest, both of which usethe tag structure described earlier in this section. The preferredcoding scheme uses “location-indicating” tags as already discussed. Analternative coding scheme uses “object-indicating” (or“function-indicating”) tags.

A location-indicating tag contains a tag ID which, when translatedthrough the tag map associated with the tagged region, yields a uniquetag location within the region. The tag-relative location of the pen isadded to this tag location to yield the location of the pen within theregion. This in turn is used to determine the location of the penrelative to a user interface element in the page description associatedwith the region. Not only is the user interface element itselfidentified, but a location relative to the user interface element isidentified. Location-indicating tags therefore trivially support thecapture of an absolute pen path in the zone of a particular userinterface element.

An object-indicating (or function-indicating) tag contains a tag IDwhich directly identifies a user interface element in the pagedescription associated with the region (or equivalently, a function).All the tags in the zone of the user interface element identify the userinterface element, making them all identical and thereforeindistinguishable. Object-indicating tags do not, therefore, support thecapture of an absolute pen path. They do, however, support the captureof a relative pen path. So long as the position sampling frequencyexceeds twice the encountered tag frequency, the displacement from onesampled pen position to the next within a stroke can be unambiguouslydetermined. As an alternative, the netpage pen 101 can contain a pair ormotion-sensing accelerometers, as described in our earlier applicationU.S. Ser. No. 09/575,174.

With either tagging scheme, the tags function in cooperation withassociated visual elements on the netpage as user interactive elementsin that a user can interact with the printed page using an appropriatesensing device in order for tag data to be read by the sensing deviceand for an appropriate response to be generated in the netpage system.

Personalized Publication Model

In the following description, news is used as a canonical publicationexample to illustrate personalization mechanisms in the netpage system.Although news is often used in the limited sense of newspaper andnewsmagazine news, the intended scope in the present context is wider.

In the netpage system, the editorial content and the advertising contentof a news publication are personalized using different mechanisms. Theeditorial content is personalized according to the reader's explicitlystated and implicitly captured interest profile. The advertising contentis personalized according to the reader's locality and demographic.

Editorial Personalization

A subscriber can draw on two kinds of news sources: those that delivernews publications, and those that deliver news streams. While newspublications are aggregated and edited by the publisher, news streamsare aggregated either by a news publisher or by a specialized newsaggregator. News publications typically correspond to traditionalnewspapers and newsmagazines, while news streams can be many and varied:a “raw” news feed from a news service, a cartoon strip, a freelancewriter's column, a friend's bulletin board, or the reader's own e-mail.

The netpage publication server supports the publication of edited newspublications as well as the aggregation of multiple news streams. Byhandling the aggregation and hence the formatting of news streamsselected directly by the reader, the server is able to place advertisingon pages over which it otherwise has no editorial control.

The subscriber builds a daily newspaper by selecting one or morecontributing news publications, and creating a personalized version ofeach. The resulting daily editions are printed and bound together into asingle newspaper. The various members of a household typically expresstheir different interests and tastes by selecting different dailypublications and then customizing them.

For each publication, the reader optionally selects specific sections.Some sections appear daily, while others appear weekly. The dailysections available from The New York Times online, for example, include“Page One Plus”, “National”, “International”, “Opinion”, “Business”,“Arts/Living”, “Technology”, and “Sports”. The set of available sectionsis specific to a publication, as is the default subset.

The reader can extend the daily newspaper by creating custom sections,each one drawing on any number of news streams. Custom sections might becreated for e-mail and friends' announcements (“Personal”), or formonitoring news feeds for specific topics (“Alerts” or “Clippings”).

For each section, the reader optionally specifies its size, eitherqualitatively (e.g. short, medium, or long), or numerically (i.e. as alimit on its number of pages), and the desired proportion ofadvertising, either qualitatively (e.g. high, normal, low, none), ornumerically (i.e. as a percentage).

The reader also optionally expresses a preference for a large number ofshorter articles or a small number of longer articles. Each article isideally written (or edited) in both short and long forms to support thispreference.

An article may also be written (or edited) in different versions tomatch the expected sophistication of the reader, for example to providechildren's and adults' versions. The appropriate version is selectedaccording to the reader's age. The reader can specify a “reading age”which takes precedence over their biological age.

The articles which make up each section are selected and prioritized bythe editors, and each is assigned a useful lifetime. By default they aredelivered to all relevant subscribers, in priority order, subject tospace constraints in the subscribers' editions.

In sections where it is appropriate, the reader may optionally enablecollaborative filtering. This is then applied to articles which have asufficiently long lifetime. Each article which qualifies forcollaborative filtering is printed with rating buttons at the end of thearticle. The buttons can provide an easy choice (e.g. “liked” and“disliked’), making it more likely that readers will bother to rate thearticle.

Articles with high priorities and short lifetimes are thereforeeffectively considered essential reading by the editors and aredelivered to most relevant subscribers.

The reader optionally specifies a serendipity factor, eitherqualitatively (e.g. do or don't surprise me), or numerically. A highserendipity factor lowers the threshold used for matching duringcollaborative filtering. A high factor makes it more likely that thecorresponding section will be filled to the reader's specified capacity.A different serendipity factor can be specified for different days ofthe week.

The reader also optionally specifies topics of particular interestwithin a section, and this modifies the priorities assigned by theeditors.

The speed of the reader's Internet connection affects the quality atwhich images can be delivered. The reader optionally specifies apreference for fewer images or smaller images or both. If the number orsize of images is not reduced, then images may be delivered at lowerquality (i.e. at lower resolution or with greater compression).

At a global level, the reader specifies how quantities, dates, times andmonetary values are localized. This involves specifying whether unitsare imperial or metric, a local timezone and time format, and a localcurrency, and whether the localization consist of in situ translation orannotation. These preferences are derived from the reader's locality bydefault.

To reduce reading difficulties caused by poor eyesight, the readeroptionally specifies a global preference for a larger presentation. Bothtext and images are scaled accordingly, and less information isaccommodated on each page.

The language in which a news publication is published, and itscorresponding text encoding, is a property of the publication and not apreference expressed by the user. However, the netpage system can beconfigured to provide automatic translation services in various guises.

Advertising Localization and Targeting

The personalization of the editorial content directly affects theadvertising content, because advertising is typically placed to exploitthe editorial context. Travel ads, for example, are more likely toappear in a travel section than elsewhere. The value of the editorialcontent to an advertiser (and therefore to the publisher) lies in itsability to attract large numbers of readers with the right demographics.

Effective advertising is placed on the basis of locality anddemographics. Locality determines proximity to particular services,retailers etc., and particular interests and concerns associated withthe local community and environment. Demographics determine generalinterests and preoccupations as well as likely spending patterns.

A news publisher's most profitable product is advertising “space”, amulti-dimensional entity determined by the publication's geographiccoverage, the size of its readership, its readership demographics, andthe page area available for advertising.

In the netpage system, the netpage publication server computes theapproximate multi-dimensional size of a publication's saleableadvertising space on a per-section basis, taking into account thepublication's geographic coverage, the section's readership, the size ofeach reader's section edition, each reader's advertising proportion, andeach reader's demographic.

In comparison with other media, the netpage system allows theadvertising space to be defined in greater detail, and allows smallerpieces of it to be sold separately. It therefore allows it to be sold atcloser to its true value.

For example, the same advertising “slot” can be sold in varyingproportions to several advertisers, with individual readers' pagesrandomly receiving the advertisement of one advertiser or another,overall preserving the proportion of space sold to each advertiser.

The netpage system allows advertising to be linked directly to detailedproduct information and online purchasing. It therefore raises theintrinsic value of the advertising space.

Because personalization and localization are handled automatically bynetpage publication servers, an advertising aggregator can providearbitrarily broad coverage of both geography and demographics. Thesubsequent disaggregation is efficient because it is automatic. Thismakes it more cost-effective for publishers to deal with advertisingaggregators than to directly capture advertising. Even though theadvertising aggregator is taking a proportion of advertising revenue,publishers may find the change profit-neutral because of the greaterefficiency of aggregation. The advertising aggregator acts as anintermediary between advertisers and publishers, and may place the sameadvertisement in multiple publications.

It is worth noting that ad placement in a netpage publication can bemore complex than ad placement in the publication's traditionalcounterpart, because the publication's advertising space is morecomplex. While ignoring the full complexities of negotiations betweenadvertisers, advertising aggregators and publishers, the preferred formof the netpage system provides some automated support for thesenegotiations, including support for automated auctions of advertisingspace. Automation is particularly desirable for the placement ofadvertisements which generate small amounts of income, such as small orhighly localized advertisements.

Once placement has been negotiated, the aggregator captures and editsthe advertisement and records it on a netpage ad server.Correspondingly, the publisher records the ad placement on the relevantnetpage publication server. When the netpage publication server lays outeach user's personalized publication, it picks the relevantadvertisements from the netpage ad server.

Interstitial Advertising

The netpage system provides a mechanism whereby advertising can beplaced automatically in otherwise empty space in a document. A typicalnetpage interaction sequence is likely to print many single pages wherethe reverse side of the page is empty.

Advertising can be placed in space within a document, particularly thereverse side of a netpage sheet where the reverse side is otherwiseempty. The advertising is non-intrusive, and although it may not be seenimmediately, it persists on the page and may be seen later.

With reference to FIG. 6, a document page 500 may have page content 501at the top of the page and empty space at the bottom of the page. FIG. 6illustrates an example of the placement of an advertisement 502 in emptyspace on the same page of the document.

With reference to FIG. 7, a document page 503 may have page content 504filling the front page, and may be blank on the reverse side 505 of thepage. FIG. 7 illustrates an example of the placement of an advertisement506 on the otherwise empty reverse side of a document.

The advertising can be placed in personalized publications, or anynetpage document, as long as there is space available. However, asusual, this advertising is the most effective when targeted to the user,i.e. demographically based.

Ownership of this “interstitial” advertising space can lie with theapplication provider that provides the document content, or with theinfrastructure provider involved in document delivery, such as theprinter provider. In any case the advertising can be chosen in variousways to relate to the content of the page or document.

CONCLUSION

The present invention has been described with reference to a preferredembodiment and number of specific alternative embodiments. However, itwill be appreciated by those skilled in the relevant fields that anumber of other embodiments, differing from those specificallydescribed, will also fall within the spirit and scope of the presentinvention. Accordingly, it will be understood that the invention is notintended to be limited to the specific embodiments described in thepresent specification, including documents incorporated bycross-reference as appropriate. The scope of the invention is onlylimited by the attached claims.

1. A computer system for generating print data for an interactivedocument, said interactive document comprising printed user informationand printed advertising material, said computer being configured for:receiving a print request from a user, said print request requestingprinting of an electronic document stored in said computer system;formatting user information in the electronic document so as to includea first user interactive element, thereby allowing the user to effect aresponse to the printed information using a sensing device; determiningthe advertising material for printing with the user information, saidadvertising material being based at least partially on the userinformation; formatting the advertising material so as to include asecond user interactive element, thereby enabling the user to effect aresponse to the advertising material, using the sensing device; andgenerating print data for printing the formatted user information andthe formatted advertising material together with coincident coded dataon a substrate, said coded data being readable by the sensing device andbeing indicative of a document identity and the first and secondinteractive elements.
 2. The computer system of claim 1, wherein theprint data is for a duplexed printer such that the advertising materialis printed on a reverse side of the substrate relative to the userinformation.
 3. The computer system of claim 1, wherein the coded dataidentifies a plurality of locations on the substrate.
 4. The computersystem of claim 1, further comprising a display for displaying theelectronic document to the user.
 5. The computer system of claim 1,wherein the print data instructs a printer to print the coded data usinga dedicated ink channel.
 6. The computer system of claim 1, which isconfigured for retaining a retrievable record of the printed document,the printed document being retrievable using the document identity ascontained in the coded data.